Written for The Tutor Team, published 8 March 2019 https://www.thetutorteam.com/blog/the-foundations-of-memory-how-to-support-your-child/
The Foundations of Memory: How to support your child
This is the first of two blogs on how you can best support your child’s memory. In the first blog we will learn about how important lifestyle factors lay the foundations for good memory acquisition, retention and recall. In the second blog we will learn mnemonic strategies to help manage the large quantities of information students will be learning.
What is memory?
Psychologists have been studying memory since the 1700’s. It fascinates us because we don’t understand why some memories are more salient, why someone else can remember the same event completely differently and why some information we just can’t seem to acquire or recall.
The University of Queensland describes memory as “The reactivation of a specific group of neurons, formed from persistent changes in the strength of connections between neurons.”
Several lifestyle factors as well as study techniques can affect the strength of these connections. The stronger the connections between the neurons (thicker myelin sheaths around the axons) the stronger the memory is and therefore the easier it will be to recall.
We will now explore three lifestyle factors and the implications they have on memory.
The brain consumes around 600 calories a day, interestingly it’s approximately an equal split between wakefulness and sleep (Rachel Kelly, Good Mood Food) indicating how active our brains are during sleep. Foods that support our memory tend to increase the blood flow to the brain. Foods that are processed and high in sugar restrict blood flow. In fact, blood with high glucose levels actually decreases activity in the hippocampus (an area of the brain associated with memory), reduces communication between neurons and has been shown to shrink brains (Scott Edwards, Harvard Neurobiology). A high sugar diet should be avoided at all costs. The NHS recommend only 30g per day, a can of Coca-Cola contains 39g!
We know that purple foods e.g blueberries, blackberries and beetroots contain nitric oxide which improves blood flow to the brain. Research has found that blueberries and blackberries can improve your performance in an exam by 10% (that could be 1 or 2 grades!) and have reversed memory loss. This is robust finding, even in my classroom students in the blueberry conditions would always outperform the other conditions! Dark chocolate has also been shown to increase blood flow to the brain, the higher the cacao percentage the better. Loma Linda University (2018) report two studies which found eating 70% cacao improved memory, neuroplasticity and mood, and reduced stress.
Research also shows that foods high in omega-3 benefit the brain. Our bodies can’t produce omega-3 so we can only acquire it from food sources. For example, salmon, fresh tuna, sardines, walnuts, flaxseed oil, fortified foods e.g. eggs, milk). Researchers have found that omega-3 improves memory, cognitive function and reduces anxiety (Manzoni et al. 2017; Scott Edwards Harvard Neurobiology).
As our brains use so many calories it’s important that we provide a slow and stable amount of glucose, as mentioned above high amounts of glucose restrict blood to the brain (Goldhill, 2015, The Telegraph). Whole grains are low in the glycaemic index (see NHS website for more info) for example, stone-ground whole wheat, oats, sweet potato, corn, peas, lentils, legumes and butter beans.
Choline has been shown to improve performance in memory tests. It has many functions in the body but in the brain it helps make acetylcholine, a neurotransmitter chemical released by neurons. It helps to move our muscles, regulate our hormones and sleep cycle. You can find choline in grass-fed diary products, beef liver, broccoli, cauliflower, cabbage, kale, brussel sprouts turnips and bok choi.
Overall, research into the Mediterranean diet suggests that this is the healthiest diet for our brains and bodies. Hardman et al. (2016) reviewed 18 studies into this area on people aged 19 to 75+ years old. The more participants adhered to the diet the more improvements they had to their memory. The Good Mood Food book suggests vegetables including lots of dark greens for B vitamins should make up half of our diet, fish and chicken, red meat 1-2 a week, healthy fats e.g. avocado, olive oil, eggs, nuts and seeds and lots of water!
Neurogenesis is the process in the brain whereby large numbers of neurons are produced. Neurogenesis is triggered by exercising, and as such it is possible to increase the volume of your hippocampi (University of Queensland). The hippocampi have long been associated with memory. Research by Erickson et al. (2011) showed that the fitter the person the larger their hippocampus and their temporal lobe were. They also found that aerobic exercise could reverse hippocampi volume loss (this happens naturally as we age). At the moment it is unclear as to which types of exercise are better, but research seems to indicate aerobic exercise is best. Heidi Godman (Harvard) reports that 2 brisk walks a week was enough to stimulate new blood vessels in the brain, improve sleep and decrease anxiety and stress. As we will learn in part 2 of this blog, stress and anxiety have a severely limiting effect on the brain.
Berchtold et al. (2010) has also found that when we exercise can affect how well we acquire knowledge and recall it. They found that learning after exercise gave the best recall, but learning was better one week after exercise. This shows the importance of sustaining exercise and embedding it into our lives. Exercise will also increase blood flow to the brain.
The function of sleep is to consolidate memories. The hippocampus updates the neocortex with information from the day that needs to be stored for future use. As the adolescent brain is still developing, particularly the prefrontal cortex (decision making, emotional intelligence) and myelination of axons, it is even more important that adolescents have plenty of sleep. Myelination is the process of strengthening the connection between two neurons, as mentioned above the stronger these connections the easier it is to recall memories (University of Queensland).
Research has consistently found that sleep deprivation affects higher brain functions i.e. complex thinking (Kopasz et al. 2010). A fascinating study by Potkin and Bunney (2012) found that students improved their memory performance by 20.6% if they were tested on learned material after sleep compared to no sleep.
The NHS recommends a minimum of 8-9 hours of sleep per day for adolescents. If your child struggles to get this take a look at the NHS website (Sleep tips for teenagers) and Sleep Hygiene.
Diet, exercise and sleep are the foundation to a better memory.
What can you do next?
Why not encourage your child(ren) and family to do some experiments? Spend a week working on each factor and reflect on the impact it’s had on you individually and as a family. Make a note and talk about how you are feeling, has your child noticed it’s easier to concentrate in school? Or are they feeling happier? What about their memory? These lifestyle choices will not only have a positive impact on memory but other aspects of your psychological and physical health. By involving your child/ren it will make them more engaged and motivated to try the experiments.